Kenickie is always seen throughout the movie wearing a typical greaser outfit: a black leather jacket with a white T-Birds logo on the back; dark-blue jeans; a bluish-white T-shirt; a golden necklace around his neck; and black engineer boots.
His facial features consists of dark-blond hair done in an Elephant's trunk, like Danny, a cigarette behind one ear; and pale blue eyes.
As a T-Bird, he usually eschews any `soft' emotions (like caring, kindness), like when he gave Danny Zuko a `What the hell are you doing, man?' look when Danny exclaimed in joy when he was reunited with Sandy Olsen. When Sandy cried that Danny was a fake and a phony, after she ran away, Kenickie made the odd comment "I wonder if she carries silver bullets". That could have been a reference to Danny's rapid transformation from nice guy to jack-ass (like human to werewolf).
He did have a deeper side, though. When he and Danny are right outside the Frosty Palace (malt shop), he seems to be annoyed at the Scorpions for driving into T-Birds territory, and their hangout of all places, but when he turns to Danny, who has a sad facial expression, he softens up asking calmly, "Hey Danny, what's up? You still thinking about that chick?" At the Drive-in theater, even though he shouldn't have referred to Rizzo's potential pregnancy as `his mistake' ("I don't run away from my mistakes"), he did care about Rizzo to take responsibility. When she coldly smiled and told him "It was somebody else's mistake", he tried to laugh it off, but it cut deeply, and he sighed sadly, "Thanks a lot, kid." and left, leaving Rizzo regretting what she said. Just before the race at Thunder Road, he and Danny have a best friend talk. Kenickie tells Danny that, since he's always been there for him, he wants him to be there with him at the race, not racing with him, but there to back him up. Of course, knowing they're best friends for as long as they can remember, Danny says yes to this, and the two of them hug, much to the confusion and concern of Doody, Sonny, and Putzie.
Kenickie Hey Rizzo, I hear you're knocked up.
—Kenickie, Drive-in theater
Kenickie The problem's in your mouth.